The present invention relates to a circuit board holder for connecting a circuit board to another component such as a mother board.
It is conventionally known to mount on a main printed circuit board (hereinafter referred to as a main board) a printed circuit board other than the main board (hereinafter referred to as a sub board) in a manner in which the sub board is supported substantially perpendicular with respect to the main board. In such a mounting structure, a board holder 90, as shown in FIGS. 8A and 8B, is employed.
The board holder 90 is fixed on the main board B1 and has a groove 92 extended in a direction essentially perpendicular to a surface of the main board B1. The sub board B2 is inserted from an end of the groove 92, and then guided to a proper mounting position along the groove 92.
Once the sub board B2 is inserted in the proper mounting position, an engagement piece 94 provided on the board holder 90 is engaged with an engagement receiving part C formed on the sub board B2. The sub board B2 is thus located in the proper mounting position and prevented from being detached from the board holder 90.
Also, at the same time the sub board B2 is inserted in the proper mounting position, a contact part (not shown) provided at an end of the sub board B2 is inserted into a connector (not shown) disposed on the main board B1, which results in electrical connection between a circuit on the side of the main board B1 and that on the side of the sub board B2. In this state, even if any load acts on the sub board B2, the board holder 90 prevents the load from concentrating on the connector of the main board B1 or the contact part of the sub board B2, thereby protecting the connector and the contact part from being damaged.
Now, in the aforementioned mounting structure for the sub board B2, when the sub board B2 is detached from the main board B1, the engagement piece 94 is pulled with a fingertip in a predetermined direction (a direction shown by an arrow A in FIG. 8B), which results in elastic deformation of the engagement piece 94 to release engagement between the engagement piece 94 and the engagement receiving part C. Then, while the state in which the engagement piece 94 is disengaged from the engagement receiving part C is maintained, the sub board B2 is pulled out. In this way, the sub board B2 is detached from the main board B1.
However, in cases where the sub board B2 is detached in the aforementioned manner, the sub board B2 must be pulled out while the engagement piece 94 is disengaged from the engagement receiving part C. Since at least two board holders 90 are usually provided, an operator needs to use both hands in operating each engagement piece 94. Consequently, another operator is required for an operation of pulling out the sub board B2. That is to say, a detaching operation for the sub board B2 cannot be carried out by one operator, which is a problem with the conventional board holder. Also, it is often the case that such a board holder 90 and a sub board B2 are disposed in an extremely narrow space, such as in a housing of a computer or the like, and therefore, it is sometimes difficult for two or more operators to simultaneously reach into such a narrow space and conduct their respective operations. Accordingly, when the detaching operation for the sub board B2 is carried out by two operators as mentioned above, there is no choice other than that the main board B1 is first taken out of the housing, and then, the sub board B2 is detached from the main board B1, or that obstacles in the housing are first removed to provide a working space within the housing, and then, the sub board B2 is detached from the main board B1. In both cases, however, the detaching operation for the sub board B2 is troublesome, which is another problem with the conventional board holder.
The present invention was made to solve the aforementioned problems. More specifically, the object of the invention is to provide a board holder with which a detaching operation for a board is able to be carried out more easily than before.
In order to attain this object, according to a first aspect of the invention, there is provided a board holder to be used for fixing a circuit board in a mounting position to a mother board, the board holder comprising a main part fixed in the vicinity of the mounting position, the main part having a groove into which the circuit board is insertable, for guiding the circuit board along the groove into the mounting position; an engagement part for retaining an engagement receiving part formed on the side of the circuit board, when the circuit board is inserted, along the groove of the main part, into the mounting position; and a movable part having a first position where the movable part does not disturb engagement between the engagement part and the engagement receiving part, and a second position where the movable part abuts and displaces the engagement part from retention of the engagement receiving part.
This board holder is to be used in fixing a circuit board (hereinafter simply referred to as a board), such as a printed circuit board or the like, on which various electronic components are to be mounted, on another printed circuit board or any other panel (hereinafter simply referred to as a mounting position).
In the board holder, the main part is fixed in the vicinity of the mounting position for the board, and the structure for fixing the main part in the vicinity of the mounting position is not particularly restricted. For example, the main part may be fixed by inserting a portion formed integrally with the main part into a mounting hole formed on the mounting position. Alternatively, the main part may be fixed by driving a screw, a pin, or the like. Further alternatively, the main part may be fixed by means of adhesive, solder or the like. Also, any other structure for fixing the main part in the mounting position is applicable. The groove formed in the main part should be in such a width and depth that the board, when inserted into the groove, can be held without wobbling. However, as long as the function of holding the board is not lost, it is permissible that the width or depth of the groove is partially varied, a part of a side wall or a bottom face forming the groove is chipped off, or a hole is formed on the side wall or the bottom face. Also, elastic pressing pieces may be provided within the groove, for securing the board, when inserted into the groove, with elastic deformation, thereby preventing the board from wobbling in cases where the board inserted into the groove is thinner than the width of the groove.
The engagement part is engaged with the engagement receiving part formed on the side of the board, when the board is inserted into the mounting position along the groove of the main part. As a specific structure for engagement between the engagement part and the engagement receiving part, well-known structures for engagement are arbitrarily adoptable. A specific shape of the engagement part can be varied according to a specific shape of the engagement receiving part formed on the side of the board. As an example, the engagement part may have an extending piece which is elastically deformable and having a tip which is bent like a hook, while the engagement receiving part may be a concave portion with which the tip bent like a hook can be engaged.
The movable part is movable to the first position or to the second position, and a specific mode of its motion is not particularly restricted. For example, the movable part may be slidable to move to a first or a second position; otherwise, it may be rotatable to move to the first or second position. However, the movable part should abut on the engagement part to displace it, thereby releasing engagement between the engagement part and the engagement receiving part, at least when moved to the second position.
Each of the aforementioned parts can be formed of any desired material, but is usually formed of plastic material. Also, those parts may be composed partially in combination with metallic parts such that the necessary rigidity and elasticity are provided for those parts.
In the board holder constituted as mentioned above, when the movable part is moved to the second position, it abuts on and displaces the engagement part, thereby releasing the engagement between the engagement part and the engagement receiving part. The movable part does not move out of the second position without an intentional operation to do so. Accordingly, once the movable part is moved to the second position, an operator is not bound by the hindrance of maintaining each engagement part disengaged from the respective engagement receiving part, and he/she can proceed to the next operation of pulling out the board.
Consequently, a detaching operation for the board can be accomplished by one operator without difficulty. And then, even in cases where the board is disposed in an extremely narrow space, such as in a housing of a computer or the like, it is possible for one operator to reach into such a narrow space and conduct his/her operation. As a result, it is no longer necessary to provide a working space for two operators to conduct their respective operations, saving a lot of trouble with the detaching operation for the board.
Now, more specific embodiments of the invention are hereinafter described.
According to a second aspect of the invention, there is provided a board holder in which the movable part is moved between the first and second positions in a direction parallel with the groove.
In the board holder according to the second aspect, since the movable part is moved in parallel with the groove of the main part, a direction in which the board is inserted or pulled out coincides with a direction in which the movable part is moved.
Consequently, when the operator reaches into the narrow space to insert or pull out the board, he/she can disengage the engagement part from the engagement receiving part simply by moving the movable part in a direction in which he/she inserts his/her hands or in a direction in which he/she pulls out his/her hands. Such a board holder enables the operator to conduct an operation of removing the movable part more easily, compared to a board holder in which such a movable part is moved in other directions.
According to a third aspect of the invention, there is provided a board holder in which the engagement part extends from the main part, the movable part comprises a wedge part for intruding between the engagement part and the main part as the movable part is displaced from the first position to the second position, the movable part releases the engagement part from the engagement receiving part by having the wedge part intrude between the engagement part and the main part, thereby separating the engagement part and the engagement receiving part.
In the board holder according to the third aspect, since the movable part comprises the wedge part and displaces the engagement part by having the wedge part intrude between the engagement part and the main part, a direction in which the wedge part is displaced is different from a direction in which the engagement part is displaced.
Consequently, even in cases where force for returning the engagement part, displaced by the wedge part, to its original position acts on the engagement part, and further, such force is transmitted to the wedge part, the force acting in such a direction is not sufficient to return the wedge part to its original position. Accordingly, the state in which the engagement part is disengaged from the engagement receiving part is likely to be maintained.